Tobacco



United States Patent ()fliice 3,372,699 Patented Mar. 12, 1968 N.C.,assignor to Winston-Salem,

It has been the common practice in the tobacco industry to prepareblends of domestic and oriental tobaccos in .order to provide smokingtobacco which has a pleasing flavor and aroma before and during smoking.However,

'such a procedure is costly and may at times become prohibitive in theevent that certain types of tobacco may be in short supply. Accordingly,it is a further object of this invention to provide a new class ofadditive materials which when applied to the tobacco products improveand enhance the flavor and aroma of these products and the smoke emittedtherefrom thereby increasing or en hancing the pleasure and other valuesthat may be derived by the consumer from the use of these products.

A further object of this invention is the provision of a process forenhancing or otherwise improving the flavor, aroma and other qualitiesof certain domestic, oriental, reconstituted or synthetic tobaccos whichmay be deficient in said flavor or aroma or other qualities.

An additional object of this invention is to provide a processofpreparing a smoking tobacco or product which when smoked has an enhancedflavor or aroma.

An additional object of this invention is to provide a process ofpreparing a smoking tobacco or product which when smoked has an enhancedflavor or aroma.

A still further object of this invention is the provision of smokingproducts, such as cigarettes, cigars or pipe tobacco, and a process forforming same whereby the flavor and aroma before and during smoking areimproved or enhanced.

Further and additional objects will appear from the followingdescription and the appended claims.

In accordance with one embodiment of this invention, a tobacco productis provided to which has been added orwhich has been treated with asmall amount of a compound selected from the group of compounds havingthe formula: i

wherein R and R are selectedifrom the group consisting of hydrogen andalkyl radicals with at least one of said substituents being an alkylgroup. Preferably the alkyl groups are lower alkyl-radicalsbf from 1 to4 carbon atoms'The compounds falling'within the scope Formula I of thegeneric Formula I are gamma-lactones having an alkyl substituent ineither the alpha or beta position. Thus, preferably R and R can bemethyl, ethyl, propyl, isopropyl, butyl and isobutyl.

The following specific examples illustrate the preparation andcharacteristics of representative tobacco additives of the presentinvention. It will be appreciated, however, that this invention is notlimited to the specific processes by which the compounds may beprepared. All temperatures are expressed in degrees centigrade.

Example I.The synthesis of 13-metliylbutyrolactone (a) Hydrobromiinationof methallyl chloride-A solution of 10 grams of methallyl chloride in 50milliliters of hexane was saturated with dry hydrogen bromide at 0l0 inthe presence of 1% benzoyl peroxide. The solution was washed severaltimes with water and the organic layer was dried and concentrated,yielding 18.1 grams of 1-bromo-3-chloro-Z-methylpropane.

(b) Preparation of 5-chlorro-3-m'ezhylbutanoic acid. A mixture of 18.1grams of 1-bromo-3-chloro2-methylpropane, 6.9 grams of potassiumcyanide, 6O milliliters of water and 3 milliliters of ethanol wasrefluxed four hours. The resulting solution was acidified with 50milliliters of concentrated hydrochloric acid and refluxed an additionalfive hours. The aqueous layer was extracted with ether and the etherlayers were dried and concentrated, yielding 13.8 grams of crude acid.

(c) Lactonization of 5-chl0ro-3-methylbumnoic acid- A mixture of 13.8grams of crude 5-chloro-3-methylbutanoic acid and 300 milliliters of 50%sodium carbonate solution was refluxed 14 hours and the resultingsolution was acidified with 5 N hydrochloric acid and extracted withether. The residue from the reaction was analyzed by vapor phasechromatography using a 10' x A" column packed with 10% diethylene glycoladipate on 80-100 mesh carrier. The main peak was shown by infrared andnuclear magnetic resonance spectra to have the formula:

Example lL-fi-Isopropylbutyro lactone Forty-two grams of2-isopropyl-l,3-propanediol, boiling point l18l20/l0 mm. was saturatedwith anhydrous hydrogen bromide at 0 to 5 (about 4 hours) and thereaction mixture was distilled to give 26.8 grams of1-bromo-2-isopropylpropanol, boiling point l02-l06/ 7 mm.

To a solution of 12 grams of potassium cyanide in milliliters of waterwere added 32.8 grams of lbromo-2- isopropylpropanol in 15 millilitersof ethanol. The solution was refluxed for 15 hours, cooled, diluted with20 milliliters of water and acidified with 50% hydrochloric acid.Extraction with ether and distillation of the residue produced 12.5grams of B-isopropylbutyrolactone, boiling point 73-76/ 1 millimeterhaving the formula:

Example lII.-p3-EthyZbutyrolactone The title compound, boiling point59/1 mm., is prepared according to the procedure of Example II using 2-ethyl-1,3-propanediol in lieu of the 2-isopropyl-1,3-propanediol. Theintermediate l-broma-Z-ethylpropanol had a boiling point of 84-86/ 8 mm.The final tobacco additive has the formula:

Example I V.oc-Ispropylbutyrolactone Ethylhydrogenisopropylsuccinate(26.1 grams, 0.14 mole) was added dropwise to a solution of 5.5 grams oflithium aluminum hydride in 400 milliliters of absolute ether. After theaddition was completed, the solution was refluxed for two hours, cooled,acidified with dilute hydrochloric acid, and extracted with ether.Concentration of the ether layer and distillation of the residue gave7.1 grams of a-isopropylbutyrolactone, boiling point 96 100/ 8millimeters, having the formula:

It has been found that the tobacco additives of the invention whenincorporated into tobacco products impart a fiavor and aroma both beforeand during smoking which many smokers consider to be desirable insmoking products. However, it is pointed out that the methods fordefining or characterizing the quality of a flavor or aroma in thetobacco art are almost purely subjective and different smokers maydefine the same flavor quite differently. Also, the compounds includedWithin the broad scope of this invention may impart different flavors oraromas depending upon the alkyl substituents therein. Thus, thecompounds comprehended by this invention, by subjective tests, impartcharacteristic flavors which are desirable in tobacco products and thesmoke therefrom even though the exact character thereof cannot bedescribed on the basis of known standards. The tobacco additive ofExample I provides a smooth smoke. The tobacco additive of Example 11imparts an aroma and flavor which some characterize as a sweet, richtobacco taste with the tobacco additive of Example III being similar;and that of Example IV imparts a sharp woody note.

In accordance with this invention, a compound embraced by genericformula I or mixtures thereof is added to tobacco or applied to asmoking article or its component parts in amounts of about 0.001 to 2.0percent by weight of the product. Preferably the amount of additive isbetween about 0.01 and 0.5 percent by weight in order to provide atobacco product having a desired flavor and aroma. However, the amountused will depend upon the amount of flavor and aroma desired and theparticular compound or mixture thereof that is used. The additive may beincorporated at any step in the treatment of the tobacco but ispreferably added after aging, curing and shredding and before thetobacco is formed into cigarettes. Likewise, it will be apparent thatonly a portion of the tobacco need be treated and the thus treatedtobacco may be blended with other tobaccos before the cigarettes orother smoking articles are formed. In such case the tobacco treated mayhave the additive in excess of the amounts above indicated so that whenblended with other tobaccos the final product will have the percentagewithin the indicated range.

In accordance with one specific embodiment of this invention, an aged,flue-cured and shredded tobacco is sprayed with a 1% ethyl alcoholsolution of ,Bdsopropylbutyrolactone in an amount to provide a tobaccocontaining 0.25 percent by weight of the additive on a dry basis.Thereafter the alcohol is removed by evaporation and the tobacco ismanufactured into cigarettes by the usual techniques. It has been foundthat the cigarette when prepared as indicated has a desired and pleasingflavor, an aroma which to some people is reminiscent of sweet richtobacco similar to that found in a tobacco-curing shed, and isdetectable and pleasing in the main and side smoke streams when thecigarette is smoked.

The additives falling within the scope of this invention may be appliedto the tobacco by spraying, dipping or otherwise, utilizing suitablesuspensions or solutions of the additive. Thus water or volatile organicsolvents, such as alcohol, ether, acetone, volatile hydrocarbons and thelike, may be used as the carrying medium for the additive while it isbeing applied to the tobacco. Also, other flavorand aroma-producingadditives, such as those disclosed in US. Patents Nos. 2,766,145,2,905,575, 2,905,576, 2,978,- 365 and 3,041,211 may be incorporated intothe tobacco with the additive of this invention.

While this invention is principally useful in the manufacture ofcigarette tobacco, it is also suitable for use in connection with themanufacture of pipe tobacco, cigars or other tobacco products.Furthermore, the compounds may be added to certain tobacco substitutesof natural or synthetic origin and by the term tobacco as usedthroughout this specification is meant any composition intended forhuman consumption by smoking or otherwise, whether composed of tobaccoplant parts or substitute materials or both.

Also, the invention has been particularly described with reference tothe addition of the compounds directly to tobacco. However, it will beapparent that the compound may be applied to the paper of the cigaretteor to the wrapper of a cigar. Also, it may be incorporated into thefilter tip, the packaging material or the seam paste employed for gluingthe cigarette paper. Thus a tobacco product is provided which includesthe specified additives and tobacco although in every instance thecompound need not be admixed with the tobacco as above specificallydescribed.

While several particular embodiments of this invention are shown above,it will be understood, of course, that the invention is not to belimited thereto, since many modifications may be made, and it iscontemplated, therefore, by the appended claims, to cover any suchmodiiications as fall Within the true spirit and scope of thisinvention.

I claim:

1. A tobacco product having added thereto an amount suflicient to alterthe flavor or aroma of the tobacco product of a compound selected fromthe group of compounds having the formula R1 R1 1 I wherein R and R areselected from the group consisting of hydrogen and alkyl groups of 1 to4 carbon atoms with at least one of such substituents being alkyl.

3. The product recited in claim 1 wherein the amount of said compound isbetween about 0.001 and 2.0 percent by weight of the product.

4. The product recited in claim 1 wherein the amount of said compound isbetween about 0.01 and 0.5 percent by weight of the product.

5. A tobacco product having added thereto and dispersed therein a smallamount sufficient to improve the flavor thereof ofB-methylbutyrolactone.

6. A tobacco product having added thereto and dispersed therein a smallamount sufficient to improve the flavor thereof ofB-isopropylbutyrolactone.

7. A tobacco product having added thereto and dispersed therein a smallamount suflicient to improve the flavor thereof of B-ethylbutyrolactone.

8. A tobacco product having added thereto and dispersed therein a smallamount sufiicient to improve the flavor thereof ofa-isopropylbutyrolaotone.

9. The product recited in claim 5 wherein the amount of flavorant isbetween about 0.001 and 2.0 percent by weight of said product.

10. The product recited in claim 6 wherein the amount of flavorant isbetween about 0.001 and 2.0 percent by weight of said product.

11. The product recited in claim 7 wherein the amount of flavorant isbetween about 0.001 and 2.0 percent by weight of said product.

12. The product recited in claim -8 wherein the amount of flavorant isbetween about 0.001 and 2.0 percent by weight of said product.

13. A process for improving the flavor of a tobacco product whichcomprises adding thereto a small amount of a compound selected from thegroup of compounds having the formula wherein R and R are selected fromthe group consisting of hydrogen and alkyl groups with at least one ofsuch substituents being alkyl.

14. A process for improving the flavor of a tobacco product whichcomprises adding thereto a small amount of a compound selected from thegroup of compounds having the formula added in an amount from about0.001 to 2.0 percent by weight of the product.

References Cited UNITED STATES PATENTS 10/1956 Rowland 131-17 3/1959Teague 131-264 X SAMUEL KOREN, Primary Examiner. MELVIN D. REIN,Examiner.

1. A TOBACCO PRODUCT HAVING ADDED THERETO AN AMOUNT SUFFICIENT TO ALTERTHE FLAVOR OR AROMA OF THE TOBACCO PRODUCT OF A COMPOUND SELECTED FROMTHE GROUP OF COPOUNDS HAVING THE FORMULA